pgsql: Use consistent type for pgaio_io_get_id() result

Use consistent type for pgaio_io_get_id() result

The result of pgaio_io_get_id() was being assigned to a mix of int and
uint32 variables. This fixes it to use int consistently, which seems
the most correct. Also change the queue empty special value in
method_worker.c to -1 from UINT32_MAX.

Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: /messages/by-id/70c784b3-f60b-4652-b8a6-75e5f051243e@eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/47932f3cdc4c221dbd9207cb21e63c862fedd189

Modified Files
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src/backend/storage/aio/aio_funcs.c | 4 ++--
src/backend/storage/aio/method_worker.c | 14 +++++++-------
2 files changed, 9 insertions(+), 9 deletions(-)